Editing Crohn's disease (section)

=== Bowel cancer ===

* Carcinomas typically arise at sites of chronic inflammation, especially TI
* Epidemiology
** OR 100 for small bowel cancer compared to normal population, but absolute risk still low
** 2.2% risk at 25 years since diagnosis
* Pathophysiology
** Follows standard dysplasia sequence
** Risk related to extent of small bowel involvement and duration of disease
** Small bowel adenocarcinoma associated with CD behaves aggressively - strong probability of extracellular mucin
** Mucinous-appearing anal fistulas and ileal areas of adhesion/retraction should always be closely examined by a pathologist to evaluate for dysplasia or malignancy
* Presentation
** Suspect in patients who develop a change in their clinical status, such as an obstruction that fails to resolve with usual treatments
** Diagnosis rarely made pre-operatively
* Poor prognosis due to frequent late detection